Specifications

Note that the environment we are talking about here is the environment in which PHP runs on

the server.

You can get a list of all PHP’s environment variables by running phpinfo(). Some are more

useful than others; for example,

getenv(“HTTP_REFERER”);

will return the URL of the page from which the user came to the current page.

You can also set environment variables as required with putenv(), for example,

$home = “/home/nobody”;

putenv (“ HOME=$home “);

If you would like more information about what some of the environment variables represent,

you can look at the CGI specification:

http://hoohoo.ncsa.uiuc.edu/cgi/env.html